The present invention relates to installations for continuous two-sided enameling of pipes, mainly large-diameter pipes.
Known in the art is an installation (see, for example, Austrian Pat. No. 267,279,) consisting of a number of successively mounted mechanisms for an enamel slip to a pipe surface and of heating appliances for drying and baking the enamel slip. The pipes to be enameled are conveyed in a horizontal position from one station to another by a conveying device.
The operations of applying and drying an enamel slip and its drying as well as the fusion of the enamel coating in the known installation are difficult because during these operations the pipes are conveyed horizontally and their outer surfaces rest on supports. For the same reason an effective enamel coating can be produced on the inner surface of pipes only while the outer surface can be given only a thin, decorative coating.
In addition, the known installation fails to ensure a closed working cycle so that the effective enamel coating (formed by one priming enamel coat and two covering layers of enamel) is obtained by passing the pipes three times through the installation which renders the installation low-productive and hinders its automation.